Hugh Capet, King of France and founder of the Capetian dynasty, was the eldest son of Hugh the Great by his wife Hadwig. When his father died in 956 he succeeded to his numerous fiefs around Paris and Orleans, and thus becoming one of the most powerful of the feudatories of his cousin, the Frankish king Lothair, he was recognized somewhat reluctantly by that monarch as Duke of the Franks. Many of the counts of northern France did homage to him as their overlord, and Richard I, Duke of Normandy, was both his vassal and his brother-in-law. His authority extended over certain districts south of the Loire, and, owing to his interference, Lothair was obliged to recognize his brother Henry as Duke of Burgundy. Hugh supported his royal suzerain when Lothair and the emperor Otto II fought for the possession of Lorraine; but chagrined at the king's conduct in making peace in 980, he went to Rome to conclude an alliance with Otto. Laying more stress upon independence than upon loyalty, Hugh appears to have acted in a haughty manner toward Lothair, and also towards his son and successor Louis V; but neither king was strong enough to punish this powerful vassal, whose clerical supporters already harbored the thought of securing for him the Frankish crown. When Louis V died without children in May 987, Hugh and the late king's uncle Charles, Duke of Lower Lorraine, were candidates for the vacant throne, and in this contest the energy of Hugh's champions, Adalberon, Archbishop of Reims, and Gerbert, afterwards Pope Sylvester II, prevailed. Declaring that the Frankish crown was an elective and not an hereditary dignity, Adalberon secured the election of his friend, and crowned him, probably at Noyon, in July 987

The authority of the new king was quickly recognized in his kingdom, which covered the greater part of France north of the Loire with the exception of Brittany, and in a shadowy fashion he was acknowledged in Aquitaine; but he was compelled to purchase the allegiance of the great nobles by large grants of royal lands, and he was hardly more powerful as king than he had been as duke. Moreover, Charles of Lorraine was not prepared to bow before his successful rival, and before Hugh had secured the coronation of his son Robert as his colleague and successor in December 987, he had found allies and attacked the king. Hugh was worsted during the earlier part of this struggle, and was in serious straits, until he was saved by the wiles of his partisan Adalberon, Bishop of Laon, who in 991 treacherously seized Charles and handed him over to the king. This capture virtually ended the war, but one of its side issues was a quarrel between Hugh and Pope John XV, who was supported by the empire, then under the rule of the empresses Adelaide and Theophano as regents for the young emperor Otto III. In 987 the king had appointed to the vacant archbishopric of Reims a certain Arnulf, who at once proved himself a traitor to Hugh and a friend to Charles of Lorraine. In June 991, at the instance of the king, the French bishops deposed Arnulf and elected Gerbert in his stead, a proceeding which was displeasing to the pope, who excommunicated the new archbishop and his partisans. Hugh and his bishops remained firm, and the dispute was still in progress when the king died at Paris on the 24th of October 996.

Hugh was a devoted son of the church, to which, it is not too much to say, he owed his throne. As lay abbot of the abbeys of St. Martin at Tours and of St. Denis he was interested in clerical reform, was fond of participating in religious ceremonies, and had many friends among the clergy. His wife was Adelaide, daughter of William III, Duke of Aquitaine, by whom he left a son, Robert, who succeeded him as king of France. The origin of Hugh's surname of Capet, which was also applied to his father, has been the subject of some discussion. It is derived undoubtedly from the Latin capa, cappa, a cape, but whether Hugh received it from the cape which he wore as abbot of St. Martin's, or from his youthful and playful habit of seizing caps, or from some other cause, is uncertain.